DECLINING SERUM TOTAL CHOLESTEROL LEVELS AMONG UNITED-STATES ADULTS -THE NATIONAL-HEALTH AND NUTRITION EXAMINATION SURVEYS

Objective.-To examine the secular trend in serum total cholesterol lev els of the US adult population. Design.-Nationally representative cros s-sectional surveys with both an in-person interview and a medical exa mination that included the measurement of blood lipid levels. Setting/ Participants.-Between 6000 and 13 000 adults aged 20 through 74 years examined in each of four separate national surveys during 1960 through 1962, 1971 through 1974, 1976 through 1980, and 1988 through 1991. Re sults.-Mean serum total cholesterol levels in US adults aged 20 throug h 74 years have consistently declined over the time period 1960 throug h 1991. More than half of the decline occurred during the time period 1976 through 1991. This decline occurred across the entire distributio n of serum cholesterol levels and in all age-sex groups. High-density lipoprotein cholesterol and very low-density lipoprotein cholesterol l evels have not changed, suggesting that the decline in total cholester ol levels is due to a decline in low-density lipoprotein cholesterol l evels. Conclusions.-These results document a continuing and substantia l decline in serum cholesterol levels among US adults. They suggest th at public health programs, designed to reduce cholesterol levels, are proving successful. The observed downward trend in serum cholesterol l evels has coincided with a continuing decline in coronary heart diseas e mortality. These observations suggest that the Healthy People 2000 g oal of reducing the mean serum cholesterol level of US adults to no mo re than 200 mg/dL (5.17 mmol/L) is attainable.